2008 (1979-2008) Sea Ice Yearly Minimum w/Graph Overlay

The continued significant reduction in the extent of the summer sea ice cover is a dramatic illustration of the pronounced impact increased global temperatures are having on the Arctic regions. There has also been a significant reduction in the relative amount of older, thicker ice. Satellite-based passive microwave images of the sea ice cover have provided a reliable tool for continuously monitoring changes in the extent of the Arctic ice cover since 1979. The ice parameters derived from satellite ice concentration data that are most relevant to climate change studies are sea ice extent and ice area. This visualization shows ice extent in the background and ice area in the foreground. Ice extent is defined here as the integrated sum of the areas of data elements (pixels) with at least 15% ice concentration while ice area is the integrated sum of the products of the area of each pixel and the corresponding ice concentration. Ice extent provides information about how far south (or north) the ice extends in winter and how far north (or south) it retreats toward the continent in the summer while the ice area provides the total area actually covered by sea ice which is useful for estimating the total volume and therefore mass, given the average ice thickness. For more information about these ice datasets, see The Journal of Geophysical Research VOL. 113, C02S07, doi:10.1029/2007JC004257, 2008